• International Journal of Highway Engineering
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• v.16 no.4
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• pp.45-50
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• 2014

PURPOSES : The objective of this study is to analyze the performance of anti-stripping agent depending on its type and content to reduce pothole, an increasing pavement distress due to abnormal climate intensity. METHODS : In the past years, U.S and many countries in Europe use hydrated lime and liquid anti-stripping agent in asphalt mixtures. Hydrated lime or liquid anti-stripping agent is substituted for filler and binder, respectively, to improve the anti-stripping property of asphalt mixtures. To investigate this, indirect tensile strength test was performed and TSR values were compared for different content of hydrated lime and types of liquid anti-stripping agent in asphalt mixture. RESULTS : Test results indicate that hydrated lime remarkably increased the asphalt mixture performance on anti-stripping denoted by the increased in TSR values from 55% to 100%. Liquid anti-stripping agent also increased the value of TSR but not significant. In addition, depending on the types of aggregate, TSR values and effect of liquid anti-stripping were different. CONCLUSIONS : Using anti-stripping agents improve the anti-stripping property of asphalt mixture especially hydrated lime; however, more experiments should be conducted to improve the reliability about the effect of liquid anti-stripping agent.

• International Journal of Highway Engineering
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• v.19 no.2
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• pp.127-135
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• 2017

PURPOSES: The objective of this study is to evaluate the effect of anti-stripping on asphalt mixtures constituting anti-stripping agents. METHODS : Based on the literature review, asphalt mixture added with anti-stripping agents was prepared, and these asphalt mixtures were evaluated for anti-stripping properties for each anti-stripping agent through various lab tests, namely, tensile strength ratio (TSR), dynamic immersion test, uniaxial compression test, and indirect tensile strength test (IDT). The liquid anti-stripping agents used in the lab test were premixed with each asphalt binder (PG 64-22, PG 76-22) before being mixed with the aggregate. RESULTS :The result of the TSR test revealed that the effect of anti-stripping was highest when hydrated lime and liquid anti-stripping agent W were added. The correlation coefficient $R^2$ between the TSR result and cohesion ratio is 0.99, which indicates that the sensitivity of the TSR to moisture damage is reliable from the mechanical point of view. The covering ratio of the asphalt binder to the liquid anti-stripping agent W was determined to be higher than that to the other liquid anti-stripping agents. CONCLUSIONS :It is considered that the improved moisture resistance of asphalt mixture as a result of the use of anti-stripping agents can reduce the incidence of various pavement damages such as portholes caused by stripping, and the performance life of the asphalt road pavement can be prolonged.

• International Journal of Highway Engineering
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• v.17 no.1
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• pp.77-82
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• 2015

PURPOSES : The purpose of this paper is to evaluate the moisture susceptibility of asphalt mixtures containing developed liquid anti-stripping agents using the boiling water test as a screening test. METHODS : The boiling water test was used to evaluate the moisture susceptibility of asphalt mixtures containing different anti-stripping agents. The tensile strength ratio was calculated to compare the moisture susceptibility of the asphalt mixtures after indirect strength tests were performed. Additionally, image analysis techniques were used to calculate and analyze the quantity of stripped area in the asphalt mixtures. RESULTS : In general, the asphalt mixtures containing anti-stripping agents showed a higher resistance of anti-stripping based on the boiling water test and tensile strength ratio. CONCLUSIONS : The boiling water test can be used to differentiate the resistance of moisture susceptibility of asphalt mixtures, except for asphalt mixtures containing hydrated lime. The boiling water test can be used as a screening test for asphalt mixtures before conducting time consuming and expensive indirect tensile strength tests.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.2
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• pp.319-325
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• 2018

Pot-holes are steadily increasing due to abnormal climate such as heavy rainfall and frequent snowfall. Pot-hole related to traffic accidents cause injuries, car damage and distress of road facilities. To reduce pot-holes, the use of an anti-stripping agent is mandatorily recommended to asphalt concrete mixture. Hydrated lime is commonly used as anti-stripping agent due to the convenience and economics. Byproduct ash from circulating fluidized bed boiler was reviewed as an anti stripping agent. According to the test results, the byproduct ash is satisfied with TSR specification using 1% to 3% by weight of the asphalt mixture. The byproduct ash was examined under various condition changes of aggregate and asphalt concrete mixture considering quality movement. According to the results, using the byproduct ash was measured average 0.87 of TSR and coverage rates of 60% after rolling bottle test. Test results also revealed that the byproduct ash showed stable performance. Using the byproduct ash to decrease pot-hole in asphalt concrete pavement is suitable for demonstrating stable performance as anti-stripping agent.

• International Journal of Highway Engineering
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• v.10 no.4
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• pp.41-52
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• 2008

This study is to evaluate the property for the moisture susceptibility of asphalt mixtures using anti-stripping agent. Asphalt mixtures using lime, hydrated lime and liquid anti-stripping agent are evaluated through the three types of modified moisture conditioning($H_c$, V_s$, F-T). Indirect Tensile Test, that is recommended by AASHTO TP-9, which includes creep test, resilient modulus test and strength test is used to estimate moisture susceptibility. Analysis method through Energy Ratio(ER) that is proposed by Roque at University of Florida is used to evaluate moisture susceptibility and moisture resistance effects of asphalt mixtures using anti-stripping agent. As a test result, material property of asphalt mixtures was changed by moisture conditioning methods and the types of anti-stripping agent. Also, cracking resistance of accumulated moisture damage was changed by moisture conditioning methods and the types of anti-stripping agent. Based on test result, it was found that cracking resistance using Energy Ratio was differed from 10% to 30%.

• International Journal of Highway Engineering
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• v.3 no.4 s.10
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• pp.105-116
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• 2001

This study was performed to evaluate the characteristics of waste foundry sand (WFS) and the asphalt mixture made of a foundry waste sand. To estimate the applicability of WFS, chemical and physical properties were measured by XRF(X-ray fluorescent), and SEM(Scanning electronic microfilm). To improve the stripping resistance of WFS asphalt mixture, anti-stripping agents (a hydrated lime and a liquid anti-stripping agent) were used. To improve tensile properties and durability of WFS asphalt concrete mixture, LDPE(low-density polyethylene) was used as an asphalt modifier Marshall mix design, indirect tensile strength, tensile strength ratio(TSR) after freezing and thawing, moisture susceptibility and wheel tracking tests were carried out to evaluate performance of WFS asphalt concrete. Comparing with conventional asphalt concrete, WFS asphalt concretes showed similar or the better qualify in mechanical properties, and satisfied all specification limits. Therefore, it Is concluded that waste foundry sand can be recycled as an asphalt pavement material.

• 한국도로학회:학술대회논문집
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• 2005.03a
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• pp.155-162
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• 2005

• 한국도로학회:학술대회논문집
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• 2000.11a
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• pp.183-189
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• 2000

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.21 no.3
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• pp.1-9
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• 2008

Objective : Prolonged use of systemic corticosteroids negatively impacts skin barrier function. Corticosteroids have a major role in the practical management of many diseases, so it is necessary to find the drug or supplement which could keep the skin healthy during the systemic corticosteroids therapy. Seed of Trichossnthcs kiiilowii was commonly used for pulmonary disease in traditional Chinese medicine. Many studies have investigated and found that seed of Trichosanthes kirilowii has anti-bacterial, anti-HIV, anti-tumor and immunoregulatory functions. This study was performed to investigate the effect of seed of Trichosmthes kirilowii on the Skin Barrier Method : Triamcinolone 0.4mg was injected male hairless mice for 5 weeks ( 2 times a week, totally 10 times), Just before the first injection, hairless mice were divided into 3 groups; Control ( normal saline medicated group ), GroupA( seed of Trichosuuhes kirilowii qd/day medicated group ) and GroupB( seed of Trichosuuhes kiiilowii bid/day medicated group ), Body weight of all the groups were checked during the experiment, After $10^{th}$ injection, TEWL (Transeidermal water loss) of 3 groups were artificially increased by 9 times tape stripping and the changes of TEWL were checked at before stripping, right after, 2h, 4h, 6h, 24h, 48 and 72h later after stripping, AST, ALT and CBC were also checked. Indeed, stratum corneum of 3 groups were also examined and compared with that of normal hairless mouse. Results : 1. GroupB showed significantly lower body weight among three groups 2, There was no statistical difference at AST, ALT and CBC among three groups 3. GroupB was showed significantly lower TEWL than TEWL of Control at 48h later. 4 GroupB recovered it's TEWL of before tape stripping at 24h later, GroupA recovered that at 48h and Control recovered that at 72h later at the same condition 5. Stratum corneum of GroupA and GroupB were looked almost normal and healthy. On the contrary, stratum corneum of Control was looked thin and unhealthy. Conclusions : Seed of Ttichossnthes kirilowii has some effects on skin barrier function, especially TEWL of high dose corticosteroids injected hairless mouse and the efficacy seemed to be related with the dosage.

• International Journal of Highway Engineering
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• v.17 no.4
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• pp.77-87
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• 2015

PURPOSES: It is theoretically well known all over the world, that porous hot mixed asphalt (HMA) with hydrated Lime improves moisture and rutting resistance, and reduces pothole occurrence frequency, as well as the life cycle cost (LCC). METHODS : Addictive in the two different formations of the liquid anti-stripping Agent and powder Hydrated-Lime was applied in this investigation in order to obtain relatively clear results according to their types and conditions. Firstly, the moisture conditions were set, and applied to the porous HMA mixtures with hydrated lime (anti-stripping agent). Next, it was followed by a non-destructive test with the application of three freeze-thaw cycles, which were individually carried out thrice to compare the results of the dynamic moduli. Lastly, the hydrated lime effect related to moisture sensibility to porous HMA has been verified through the analysis of the modulus results regarding the change rate of dynamic modulus per n-cycle. RESULTS: It is clear from this investigation, that the dynamic modulus is inversely proportional to the change in temperature, as the graph representing the rigidity of the thermorheologically simple (TRS) material showed gradual decline of the dynamic modulus with the increase in temperature. CONCLUSIONS: The porous HMA mixture with the anti-stripping agent (hydrated Lime) has been found to be more moisture resistant to freezing and thawing than the normal porous HMA mixture. It is clear that the hydrated lime helps the HMA mixture to improve its fatigue resistance.